He is, however, "seriously considering" another run for his Senate seat, which he's held since 1987.

McCain said that despite a vote of disapproval from the Arizona GOPthat he isn't conservative enough, "I can sense the people of my state.... They like me, and I'm very grateful."

McCain was the Republican presidential nominee in 2008, but lost to then-Sen. Barack Obama of Illinois. Sen. Ted Cruz of Texas rebuked losing GOP nominees such as McCain, Mitt Romney and Bob Dole in a CPAC speech last week, saying they lost because they didn’t' stick to principles.

"All's fair in politics. And Sen. Cruz, who I have a cordial relationship with, can say what he wants about me," McCain told host Neil Cavuto on Monday.

"There's no way you can be friendly after that," Cavuto said.

"I did go up to him on the floor and said, 'Look, if you want to do that to me and Mitt, fine, but Bob Dole, come on. Bob Dole worked hand-in-glove with Ronald Reagan,'" McCain acknowledged.

McCain said Reagan, unlike what some have said, would recognize his old party today, but added, "I don't think he would be in lockstep with what is being advocated here, and that is if you're not with me 100 percent of the time, then you're against me."